diff --git a/src/afs/afs_osi.c b/src/afs/afs_osi.c
index 6f54c63c7a..e8f852e2e4 100644
--- a/src/afs/afs_osi.c
+++ b/src/afs/afs_osi.c
@@ -25,11 +25,6 @@
  *     -- On HP called from afsc_link.
  *     -- On SGI called from afs_init. */
 
-/* No hckernel-specific header for this prototype. */
-#ifndef UKERNEL
-extern void init_hckernel_mutex(void);
-#endif
-
 afs_lock_t afs_ftf;		/* flush text lock */
 
 #ifdef AFS_SGI_ENV
diff --git a/src/afs/afs_osi.h b/src/afs/afs_osi.h
index 79c44a985e..e3f0e0ccb2 100644
--- a/src/afs/afs_osi.h
+++ b/src/afs/afs_osi.h
@@ -458,4 +458,9 @@ extern int osi_ShouldDeferRemunlink(struct vcache *avc);
 # define osi_ShouldDeferRemunlink(avc) 0
 #endif
 
+/* No hckernel-specific header for this prototype. */
+#ifndef UKERNEL
+extern void init_hckernel_mutex(void);
+#endif
+
 #endif /* _AFS_OSI_ */